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81.
Tanning materials of historic leather samples collected from the 19th century Portuguese Royal train were analyzed by attenuated total reflection–Fourier transform infrared (ATR–FTIR) spectroscopy. Studied leathers were visually identified as morocco leathers, one of the most valued types of vegetable tanned leathers. In technical and historic literature, morocco leathers are described as a distinctive type of vegetable tanned leather, with a typical grain surface pattern, made from goat skins and sumac (Rhus coriaria) leaves.ATR–FTIR spectra of the Royal train leathers were investigated and compared with 10 reference tanning materials obtained from different plants in use in the 19th century, here described. Two different types of vegetable tanned leathers were identified. The obtained spectra allowed to confirm the presence of morocco leathers as well as to detect a different type of vegetable tanned leather, probably applied as a restoration material in a past intervention. This study shows the usefulness of ATR–FTIR to distinguish different types of historic leathers based in the spectroscopic characteristic IR bands of vegetable tannins used for leather production, which can be of great assistance for conservation condition assessments. 相似文献
82.
The parallel ion energy distribution of a synthesized plasma can be readily controlled via plasma potential gradients in the
ion source chamber(s). Alternatively, layers of electrically biased metal filaments can introduce an isotropic ion heating. 相似文献
83.
84.
WANG Jian-Ping FU Yong-Ju WANG Jian-Ge QIN Jian-Hua CHEN Qing-Hua 《结构化学》2007,26(5):515-518
A novel morpholine derivative was synthesized by Michael addition/internal nucleophilic substitution of 4-(L)-menthyloxy(1R,2S,5R)-butenolide with phenyl-glyalcohol under mild condition, and its structure was determined by X-ray diffraction. The target compound belongs to orthorhombic, space group P212121 with a = 5.7729(7), b = 11.5032(14), c = 25.161(3) , Mr = 319.35, Z = 4, V = 1670.8(4) 3, Dc = 1.270 g/cm3, μ(MoKα) = 0.094 mm-1, F(000) = 680, Flack = 0.01(2), R = 0.0398 and wR = 0.0914. 相似文献
85.
The title compound N-(7-chloro-5-ethoxy-2H-[1,2,4]thiadiazolo[2,3-a]pyrimidin- 2-ylidene)- 2-(2,4-dichlorophenoxy)propanamide 3 has been synthesized through using bromine as cyclic reagent in 63% isolated yield. Suitable single crystals for X-ray diffraction were obtained by recrystallization from the mixture solvents at room temperature. Crystallographic data of 3: C16H13- Cl3O3S, Mr = 447.71, triclinic, space group P, a = 8.7461(8), b = 9.9560(10), c = 11.8572(11) , α = 94.341(2), β = 94.683(2), γ = 112.929(2)o, Z = 2, V = 941.21(15) 3, Dc = 1.580 g/cm3, F(000) = 456, R = 0.0794, wR = 0.2056 and μ(MoKα) = 0.623 mm-1. The title compound 3 was found to be effective in herbicidal activity. 相似文献
86.
Two new transition metal complexes, [Ni(bipy)2Cl]·ClO4 (bipy = 2,2'-bipyridine) 1 and [Zn(bipy)2Cl]·BF4 2, have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 crystallize in monoclinic space group P21/n with Z = 4. For 1, a = 10.776(1), b = 12.067(1), c = 16.146(2)(A), β= 93.021(2)o, V = 2031.9(4)(A)3, Mr = 505.98, Dc = 1.654 g/cm3, μ = 1.255 mm-1, F(000) = 1032, the final R = 0.0406 and wR = 0.1002 for 3983 observed reflections with Ⅰ > 2σ(I). For 2, a = 10.758(4), b = 12.058(4), c = 16.135(5) (A), β = 104.57(1)o, V = 2025.7(12) (A)3, Mr = 500.00, Dc = 1.639 g/cm3, μ = 1.396 mm-1, F(000) = 1008, the final R = 0.0470 and wR = 0.1237 for 3759 observed reflections with Ⅰ > 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. A one-dimen- sional zigzag double hydrogen-bonding-chain is generated by the intermolecular M-bipy …anion…bipy--M hydrogen bonding interactions between the chelating ligands of bipy and anion. 相似文献
87.
A metal-organic coordination compound formulated as [Cd(MDPPz)(BDC)(H2O)]n 1 (MDPPz = 11-methyldipyrido[3,2-a:2',3'-c]phenazine, BDC = 1,4-benzenedicarboxylate) has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, fluorescence spectrum and single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group C2/c, with a = 30.673(8), b = 9.623(3), c = 20.784(6) (A), β = 98.646(3)o, V = 6065(3) (A)3, C27H17CdN4O5, Mr = 589.85, Dc = 1.292 g/cm3, μ(MoKα) = 0.757 mm(1, F(000) = 2360, Z = 8, the final R = 0.0381 and wR = 0.0855 for 4191 observed reflections (I>2σ(I)). 1 exhibits blue fluorescence property at room temperature. 相似文献
88.
1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2,Mr=472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol,and determined by X-ray structure analysis. It crystallizes in the orthorhombic system,space group P21/c with a=7.9839(16),b=12.910(3),c=12.358(3),α=90.00,β=93.71(3),γ= 90.00°,V=1271.1(4)3,Z=2,Dc=1.235 g/cm3,μ=0.077 mm-1,F(000)=500,the final R= 0.0717 and wR=0.1187. It presents a linear centrosymmetric framework constituted by a linkage of benzidine as a bridge and two terminal 1-phenyl-1,3-butanedione moieties. 相似文献
89.
The title compound E,E-1,4-bis[4'-(N,N-di-n-butylamino)styryl]-2,5-dimen- thoxybenzene (abbreviated to DBMB) has been synthesized by the wittig reaction of [(2,5- dimethoxy-1,4-phenylene)]bis(methylene)]bistriphenylphosphonium dichloride with 4-(N,N-di-n- butylamino)benzaldehyde. Its crystal structure was determined by a four-circle diffractometer. Crystal data: C40H56N2O2, Mr = 596.87, triclinic, space group P, a = 0.9303(2), b = 0.9625(2), c = 1.0442(2) nm, α = 81.493(12), β = 78.387(12), γ = 87.876(11)°, V = 0.9057(4) nm3, Z = 1, Dc = 1.094 g/cm3, F(000) = 326, μ(MoKa) = 0.066 mm-1, the final R = 0.0925 and wR = 0.2092. The results reveal that the molecule is a completely reverse structure with fine symmetry and a conju- gated system. 相似文献
90.